How to prove that the equation $x^2-3y^2=17$ has no integer solutions?

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How to prove that the equation $$x^2-3y^2=17$$ has no integer solutions? Can you help me?

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$$x^2-3y^2=17\implies x^2\equiv2\pmod 3$$

but $x$ can be $\equiv 0,\pm1\pmod 3\implies x^2\equiv0,1\pmod 3$